s 



f 



mm 



influences which these islands afford may be fairly expected to " break out" when 

 transported to Madeira and the Canary Islands ; and so, if it can but be agreed 

 that the English and the Irish ivy are in the end one and the same plant, there is 

 nothing more surprising in the relationship thus established than the earnest ivy- 

 hunter will meet with when in the same wood he finds a plant of helix producing 

 leaves not larger than a sixpence, and another producing leaves that he cannot 

 cover with the palm of his hand. The " rough and ready" system of settling 

 the "origin of species" is not altogether valueless. 



It has been assumed hitherto that all ivies tend to a fruiting state and to the 

 production of fruit in common with most other plants. There may be, however, 

 forms that are absolutely sterile, although no satisfactory proof has been obtained 

 to remove the statement out of the realm of conjecture. Dr. Hooker says "the 

 small sylvestral form, with longer leaf lobes and often pale nerves, never flowers." l 

 The small sylvestral form, selected to furnish the enclosing borders of this work, 

 does frequently flower and bear abundance f fruit, and, of necessity, it has first 

 to climb to the tops of trees and form arborescent tufts long before it acquires a 

 state of fruitfulness. But as flowers destitute of stamens and flowers destitute of 

 ovaries may be found by those who will search for them, and entire corymbs con- 

 sisting of monoecious flowers, it becomes highly probable that some varieties are 

 permanently unproductive of fruit. But to say of any form that it u never flowers" 

 is rather to declare insufficiency of observation and undue haste in arriving at a 

 definite conclusion. 



The sketch on page 60 was hastily made from a group of leaves arranged as 

 represented, to illustrate their extreme diversities of size and form. The largest 

 leaf shows the average shape and dimensions of the Irish ivy, the others are forms 

 of Hedera helix. If we declare these to be forms of one species only, how 

 wonderful is its range of variations ! 



This dry chapter may, we trust, be appropriately concluded with a few lines 

 from Sir Richard Blackmore : 



" Your contemplation farther yet pursue ; 

 The wondrous world of vegetables view! 

 Observe the forest oak, the mountain pine, 

 The towering cedar, and the humble vine, 

 The bending willow, that o'ershades the flood, 

 And each spontaneous offspring of the wood ! 





Student's Flora," p. 172. 





